Abstract: Selective soldering system for selective wave soldering of circuit boards, including a solder pot, a solder nozzle which can be detachably arranged on the solder pot, wherein the solder nozzle has a nozzle base and a nozzle neck, wherein at the free end of the nozzle neck a nozzle opening is provided, the solder pot being arranged on a moving unit, which can be moved along an x and y axis in a horizontal plane and along a z axis in the vertical direction, and a control unit for controlling the moving unit.

Abstract: Selective soldering system for selective wave soldering of circuit boards, including a solder pot, a solder nozzle which can be detachably arranged on the solder pot, wherein the solder nozzle has a nozzle base and a nozzle neck, wherein at the free end of the nozzle neck a nozzle opening is provided, the solder pot being arranged on a moving unit, which can be moved along an x and y axis in a horizontal plane and along a z axis in the vertical direction, and a control unit for controlling the moving unit.

Abstract: A pivot-steered tandem roller for ground compaction, comprising a machine frame with an operator platform, two compaction drums which are spaced apart from one another in the longitudinal direction of the machine and are each steerably mounted on the machine frame via a pivot steering system, a drive motor, a cooler, and a fan associated with the cooler and conveying a cooling air flow, the cooler being arranged vertically above and/or in the longitudinal direction of the machine at the level of one of the compaction drums. Moreover, the invention relates to a method for operating such a pivot-steered tandem roller.

Abstract: A microfluidic device (10) comprising: a main body; at least one source reservoir and at least one collection reservoir (18,20); at least one fluid channel (12) for channelling a fluid comprising a compound from the at least one source reservoir (18) to the at least one collection reservoir (20); a plurality of chambers (13) for holding cells, wherein the plurality of chambers (13) are formed underneath and open to the fluid channel (12), wherein a fluid flow is generated through the at least one fluid channel (12) by a difference in hydrostatic pressure between fluid in the at least one source reservoir (18) and fluid the at least one collection reservoir (20) such that the fluid flow provides a compound concentration gradient across the plurality of chambers (13) and wherein the at least one collection reservoir (20) has an overflow opening (32) to substantially maintain a level of hydrostatic pressure in the at least one collection reservoir (20).

Abstract: A microfluidic device (10) comprising: a main body; at least one source reservoir and at least one collection reservoir (18,20); at least one fluid channel (12) for channelling a fluid comprising a compound from the at least one source reservoir (18) to the at least one collection reservoir (20); a plurality of chambers (13) for holding cells, wherein the plurality of chambers (13) are formed underneath and open to the fluid channel (12), wherein a fluid flow is generated through the at least one fluid channel (12) by a difference in hydrostatic pressure between fluid in the at least one source reservoir (18) and fluid the at least one collection reservoir (20) such that the fluid flow provides a compound concentration gradient across the plurality of chambers (13) and wherein the at least one collection reservoir (20) has an overflow opening (32) to substantially maintain a level of hydrostatic pressure in the at least one collection reservoir (20).